You may need a combination of products. The road routing products typically don't handle off-road and pedestrian travels as you want. There are products, however, that will do the pedestrian tasks nicely. They are called "moving map" applications. Look
here for a list from last year of that type product, or
here for geocaching products that may also do what you want.
Mapopolis can be set for off road handling, and it does a nice job at tracking the actual fix position without the "snap to road" that the road routing system typically force. It also allows for a distance measurement on the maps. The beauty is that Mapopolis is free, you pay for maps, but you can try it with a demo map to see if it does what you want/need. Most other packages don't have demo versions. If you have the X50v, get the latest beta version from their support forum at
www.gpspassion.com as it fixes some problems with VGA display.